Washington it is 4 weekly.
DUB-12.45-IAD-15.35
IAD-17.20-DUB-05.30
Also 3rd daily 752 service to JFK confirmed.
DUB-07.50-JFK-10.20
JFK-12.00-DUB-23.40
Shannon gets a 767 based for 12 peak weeks of the summer while the 752 does the extra DUB-JFK. SNN-BOS will see the increased capacity only.
Over all an extra 14 weekly return flights peak season with 7 weekly outside of this.